the one where they are diagonal from one another
Answer:
17.5 in
Step-by-step explanation:
Step one:
given
The perimeter of a rectangle is 53 inches
let the two shorter sides be the width w
so w+w= 18in
the two longer sides is L
L+L=2l
Step two:
but the expression for the perimeter of a rectangle is
P=2W+2L
53= 18+2L
53-18=2L
35=2L
divide both sides by 1
L=35/2
L=17.5
John's effective annual rate is about
(1 +.0576/4)^4 -1 ≈ 5.8856%
According to the "rule of 72", John's money will have doubled in
72/5.8856 = 12.23 years
John's balance will be $4500 in 1989.
_____
Since you're only concerned with the year (not the month), you don't actually need to determine the effective annual rate. The given rate of 5.76% will tell you 72/5.76 = 12.5 years. The actual doubling time is closer to 12.12 years, so using the effective rate gives results that are closer, but "good enough" is good enough in this case.
